Errormessage:- The type or namespace name 'ConfigurationElementType' does not exist in the namespace 'System.ServiceModel.Configuration' (are you missing an assembly reference?)
- The type or namespace name 'ConfigurationElementTypeAttribute' does not exist in the namespace 'System.ServiceModel.Configuration' (are you missing an assembly reference?)

I have seen the description of ServiceModelConfigurationElementCollection<(Of <(ConfigurationElementType>)>) Class.Namespace: System.ServiceModel.Configuration
Assembly: System.ServiceModel (in System.ServiceModel.dll)It does not work.

Problem:
- Which Namespacee, Reference or Assembly do I have to use with ConfigurationElementType?
- Where is this documented?

Just add a reference to that assembly located in the Ent Lib's installation folder, \install location\Program Files\Microsoft Enterprise Library 4.0 - May 2008\bin. Then add a using statement in your class.